NOt sure if this is the correct section to post on Im not really a forum person but here goes.

First off my 1995 ford ranger with a 3.0 v6 and 5 speed needed a new water pump. Which i should have just done the work myself but due to time constraints had to take it in. >.<

Anyways new water pump and thermostat along with new coolant and not even a day later this is what started to happen. Once it got up to normal operating temperature it would pulsate enough to where i could feel it through my clutch/break/and gas pedal. I opened my hood and sure enough my hole block shook everytime the noise was made.

Took it back in to the mechanic. He replaced the thermostat, got home left for school the next morning sure enough it was still doing it.

I then realized that after it got up to normal op temp I decided to open my hood and investigate with the engine on, My radiator upon placing my hand on the cap and directly on top and behind the fan was "cool" it was not even lukewarm...

Popped the cap and a little fluid came out but no where near that you would have expected. My fluid is not cycling. So I took it back in and he drilled 2 bleed holes in the thermostat, now it does not get hot as quick but when it does get to the normal area it will not do it or it seems not to, He said if that stops it to come back and he will put in a failsafe one, which I will honestly do myself to save the time.

Also upon after drilling holes in the cap he deduced that the radiator was cycling the fluid.

The even odder part is that It has not overheated at all in this whole process. Which with non cycling fluid wouldnt you think that I would atleast see a RISE in the temp gauge?

Also forgot to say that a new heater control valve was installed too. And due to issues that the original radiator had before I put in the new one the block was clogged with a lot of sludge. So this new rad being clogged COULD be possible with what sediment was not flushed out.